The invention provides an improved striker attachment for wood comminuting rotors which facilitates a keyed attachment enabling both a single fastener to be utilized attaching the striker to the striker retainer, and rapid removal and replacement of the striker.
Prior art comminuting apparatus for reducing large diameterwood products and stumps to a desired size, have comprised a reduction chamber, with an impact rotor positioned concentrically therein, in combination with a housing, drive motor and infeed chute. The impact rotor is formed with a plurality of horizontally elongate impact strikers at its periphery. The rotor is positioned so that the elongate wood product or stump falling under the influence of gravity through the infeed chute is directed against the strikers, and repelled ahead of the rotor""s rotational direction against an anvil formed along one side of the reduction chamber.
Prior art wood comminuting apparatus are often capable of comminuting trees or parts thereof up to 40 inches in diameter (see e.g. U.S. Pat. No. 5,165,611). Strikers used for the comminution are bolted directly to mounting projections on the rotor which is rotated to produce the comminution. Maintenance to change strikers has required complete removal of the striker mounting bolts with the consequent potential loss of bolts and uneconomical use of maintenance time, especially in view of the substantial number of strikers on a rotor of such apparatus. Strikers of the prior art are typically fastened with two (2) hex head or similar studs, stud-bolts or bolts, relying on fastener torque to position and retain the strikers, resulting in the above noted potential loss of bolts and uneconomical use of maintenance time.
It is an object of the invention to improve maintenance time and ease of striker replacement in comminution apparatus minimizing the potential for loss of components including fasteners.
It is a further object of the invention to improve the fixed positioning of the strikers for initial installation of the strikers, during operation of the comminuting device, and during maintenance or replacement of strikers.
According to the invention there is provided a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising: a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining at least one slot; a striker retainer having a leading face for attachment to the striker, said leading face defining at least one raised key, and an opposed following face; a threaded fastener for joining said striker to said striker retainer, whereby the slot of the striker closely mates with the key of the striker retainer.
Also according to the invention there is provided a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising: a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining at least one raised key; a striker retainer having a leading face for attachment to the striker, said leading face defining at least one slot; a threaded fastener for joining said striker to said striker retainer, whereby the key of the striker closely mates with the slot of the striker retainer.
In an alternative embodiment there is provided a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining first and second slots transverse of one other, the first being parallel to the at least one cutting edge; a striker retainer having a leading face for attachment to the striker, said leading face defining first and second raised keys, to be received by said slots; wherein the second raised key closely engages the corresponding slot; and the striker retainer defines a striker support surface engaging a cooperating surface on the striker to provide primary support for the striker by virtue of a cooperating surface on the striker and a clearance between the first slot and the raised key received thereby.
According to the invention there is also provided a method to attach a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising the steps of: providing a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining first and second slots perpendicular to one another; providing a striker retainer having a leading face for attachment to the striker, said leading face defining first and second raised keys to closely engage the slots; providing a bore through the striker retainer for a fastener means; providing a single fastener joining means in the striker; mating the striker slots with the striker retainer raised keys; and installing a single fastening means through the bore and mating with the fastener joining means in the striker for joining said striker to said striker retainer, whereby the slots of the striker closely mate with the keys of the striker retainer.
Also according to the invention there is provided a method to attach a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising the steps of: providing a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining first and second raised keys perpendicular to one another; providing a striker retainer having a leading face for attachment to the striker, said leading face defining first and second slots to closely engage the keys; providing a bore through the striker retainer for a fastener means; providing a single fastener joining means in the striker; mating the striker raised keys with the striker retainer slots; and installing a single fastening means through the bore and mating with the fastener joining means in the striker for joining said striker to said striker retainer, whereby the keys of the striker closely mate with the slots of the striker retainer.
In another embodiment of the invention, there is provided a method to attach a comminuting striker assembly for mounting on a rotor of a comminuting apparatus, comprising the steps of providing a striker having first and second opposed faces, the first face defining at least one cutting edge, and the second face defining first and second slots perpendicular to one another, the first being parallel to the at least one cutting edge; providing a striker retainer having a leading face for attachment to the striker, said leading face defining first and second raised keys to be received in the slot; providing a support surface on the striker retainer, separate from the keys, to engage a cooperating surface provided on the striker to provide primary support for the striker; providing a bore through the striker retainer for a fastener means; providing a single fastener joining means in the striker; mating the striker slots with the striker retainer slot; and installing a single fastening means through the bore and mating with the fastener joining means in the striker for joining said striker to said striker retainer, whereby the second raised key closely mates with the corresponding slot and the cooperating surface on the striker rests on the support surface on the striker retainer to provide primary support for the striker by virtue of a clearance provided between the first slot and the first raised key.